KLK5 gene

The KLK5 gene (KLK5 stands for: Kallikrein-Related Peptidase 5) is a protein-coding gene located on chromosome 19q13.41. The KLK5 gene is one of the newly identified members of the kallikrein gene family, a subgroup of the serine protease enzyme family. In normal human tissue, KLK5 is highly expressed in the skin, mammary gland, and testes.

Kallikreins are a subgroup of serine proteases with diverse physiological functions. There is evidence that many kallikreins are involved in cancer development. Some have the potential to serve as new biomarkers for cancer and other diseases.

The KLK5 gene is one of the fifteen members of the kallikrein subfamily, which are clustered on chromosome 19. Its expression is upregulated by estrogens and progestins. The encoded protein, a serine protease (kallikrein-5), is secreted and may be involved in desquamation in the epidermis.

Alternative splicing results in several transcript variants that encode the same protein. The encoded enzyme, kallikrein-5 (formerly known as the stratum corneum tryptic enzyme), is involved in the physiological process of skin desquamation.

Diseases associated with KLK5 include Netherton syndrome and ovarian cancer.

Related signaling pathways include keratinization and collagen chain trimerization. Specific activities associated with this gene include serine-type endopeptidase activity and serine-type peptidase activity.

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